What the hell?
John Tierney, pontificating from his posterior:
They're stuck in bumper-to-bumper traffic while the righteous fly past them in the far left lanes. Those freeway lanes used to be reserved for car pools, but they've just been opened to a new group: those of us virtuous enough to drive the right hybrids.
But even if these new privileges put more fuel-efficient cars on the road, I'm afraid the net effect will be dirtier air and more gasoline consumption. The promoters of hybrids are committing the sin identified by the ecologist Garrett Hardin in "The Tragedy of the Commons," the 1968 essay providing one of the foundations of environmentalism.
As traffic slows down, there will be more idling cars burning more gas and emitting more pollution, but politicians will be reluctant to offend hybrid owners by revoking their privilege. So it will be harder than ever to make the one change proven to speed up traffic and help the environment: convert the car pool lanes into what engineers call high-occupancy toll lanes.
There are X cars on the road, including Y carpools and Z hybrids. Increasing Z reduces overall gas usage because hybrids are considerably more fuel efficient than non-hybrids. Increasing Y reduces overall gas usage because there are fewer cars on the road total when people carpool.
Tierney's thesis? By increasing these highly-fuel efficient groups, we may increase gas usage since they slow down more often. Umm, John? An individual car pool or hybrid may burn more gas if the preferred lanes slow down, but overall gas usage will still decrease if there are fewer and more efficient cars.
Conflating individual gas usage and overall gas usage allows you to make neat public policy arguments for a fast commuter lane under the cover of reducing gas usage, but it bears mentioning that it's a fallacious argument.
Opening car pool lanes to hybrids is about encouraging people to buy hybrids. A policy that closes those car pool lanes or requires them to pay a (reduced) toll will remove or diminish that incentive. If you want a fast lane, fine. If you are hostile to the superior attitudes taken by some hybrid owners, fine.
But none of those things have to do with saving gasoline.